Defence will provide the Armed Forces of Ukraine (AFU) with 49 M1A1 tanks.
The value of the vehicles - which are being withdrawn from Australian service as new M1A2 SEP v3 Abrams arrive - and the accompanying aid package is $245 million.
"The tanks provided by Australia, one of the largest allocations of tanks by any ally, are likely to be used by mechanised brigades of the ground forces of the Armed Forces of Ukraine who are engaged along a 1400 long kilometre front," Ukraine's Ambassador to Australia Vasyl Myroshnychenko said in a statement.
ADM understands that Australia will only play a limited role in training Ukrainian crews on the vehicles, due to the need to rapidly convert the M1A1 workforce across to the M1A2 SEP v3.
Australia isn't transferring its whole fleet either. Ten M1A1s will be retained in Australia to support the transition to M1A2 SEP v3. The fate of those tanks once the transition is complete is unclear.
"These tanks will deliver more firepower and mobility to the Ukrainian Armed Forces, and complement the support provided by our partners for Ukraine," said Pat Conroy, the Minister for Defence Industry and Capability Delivery.
“As we face a challenging geostrategic environment, it is important that we continue to work together with our partners around the world to deter aggression and coercion and protect the global rules-based order.”